Arthritis

Question 1

General information about osteoarthritis?

Answer 1

• It is the most common form of arthritis
• Most common joint disease
• It is more common in individuals over 45 years and Women (as their joints are more lax)
• It occurs at (weight-bearing joints) like the ends of fingers, thumb, neck, lower back, knees, and hips mainly
• It occurs due to wear and tear, meaning that we cannot prevent it but delay it

Question 2

What is osteoarthritis?

Answer 2

It is a disease of joints that affects all weight-bearing components of the joint including:

1) Articular cartilage (it is the main tissue affected, exposing the bones to friction with one another)

2) Menisci

3) Bone

• The friction between the bones will cause the bone to become smooth, and then cracks can occur in the subchondral bone which can lead to subchondral cysts, injuring the joint will affect the muscle as the patient might not move it due to the fear of pain leading to its atrophy

Question 3

What are the normal constituents of the cartilage?

Answer 3

1) Cells (1-2%), chondrocytes that lie in their lacunae, normally 1-2 chondrocytes per lacunae and there is no sign of atypia

2) Liquid (70-80%) is the most important part as it is the major component

3) Solid pat (20-30%) mainly type 2 collagen and proteoglycans

Question 4

What are the risk factors for osteoarthritis?

Answer 4

1) Age: the strongest risk factor

2) Gender: manly females

3) Joint alignment: individuals with joints that move or fit incorrectly (like bow legs, dislocated hip) are more likely to develop OA

4) Gene defect: Defects in the gene responsible for the production of collagen

5) Joint injury or overuse

6) Obesity: One of the strongest factors for OA

Question 5

What are the different types of osteoarthritis?

Answer 5

1) Primary/idiopathic:
- More common
- Diagnosed when there is no cause for the symptoms

2) Secondary:
- Diagnosed when there is an identifiable cause
- Usually trauma or an underlying joint disorder

Question 6

How do we diagnose osteoarthritis?

Answer 6

1) Medical history

2) Physical examination

3) X-ray

4) Other tests (to exclude other causes of arthritis for example (RA), infectious arthritis, and seronegative arthritis)

Question 7

What are the symptoms of osteoarthritis?

Answer 7

• It occurs slowly, it might take years for the damage to be noticed
• Only 1/3 of the people whose X-ray shows OA report pain or other symptoms

1) Steady/intermittent pain in a joint it could be bilateral or unilateral unlike RA

2) Stiffness that follows periods of inactivity (sleep or sitting) takes less than 1hr to loosen up unlike RA where it will take more than 1hr to loosen

3) Swelling/tenderness in one or more joints, and it does not necessarily occur on both sides of the body at the same time

4) Crepitus

Question 8

How does osteoarthritis occur?

Answer 8

A) Articular cartilage:

1) The first structure to be affected

2) Erosion (ulceration of the cartilage) occurs often centrally and in weight-bearing joints

3) Fibrillation, which causes softening, splitting, & fragmentation of the cartilage

4) Splitting of the collagen fibers

5) Disorganizing the proteoglycan/collagen relationship

6) Water is attracted into the cartilage, softening it further and flaking it which might break off and impact the joint surface locking it and causing inflammation

B) Bone:

1) They become hard and polished due to the loss of cartilage protection

2) Cystic cavities form in the subchondral bone as “eburnated” bone is brittle and microfracture can occur

3) Venous congestion in the subchondral bone

4) Osteophytes (due to the haphazard reparative mechanism of the osteoblasts) form at the margin of the articular surface, osteophytes can compress the nerve making them painful

C) Ligaments:

1) Undergoes atrophy

D) Muscles:

1) Atrophy, due to pain that limits their movement

Question 9

Describe the morphology of osteoarthritis

Answer 9

1) Granular, irregular cartilage (due to its softening from degeneration)

2) Full thickness of some parts of the cartilage is sloughed, exposing the subchondral bones, which will become the new articular surface

3) Bone eburnation (polished ivory) looking bone due to the smoothening of the bone as a result of the friction

4) Osteophytes are present at the margins of the joint in an attempt to stabilize the bone

Question 10

How does a cyst occur in the bones in case of osteoarthritis?

Answer 10

Synovial fluid might leak into cracks which can form in the bone’s surface when the replaced cartilage wears away which can lead to cysts in the bone and other deformities

• The cystic degeneration will cause the eburnation of the bone and destruction of the bone and the leaking of the synovial fluid inside this bone leading to more cracks
• The cyst could be empty or filled with synovial fluid

Question 11

What is one of the important signs of osteoarthritis?

Answer 11

• Nodal osteoarthritis (prominent osteophytes)
• It is a bony enlargement of the distal and proximal interphalangeal joints (heberden’s nodes “distal” and Bouchard’s nodes “proximal”), this is due to the presence of osteophytes at these joints

Question 12

What are the radiological findings in osteoarthritis?

Answer 12

• Wear and tear erodes the hyaline cartilage over time

1) Narrowing of the joint space due to the decreased cartilage

2) Formation of osteophytes in the periphery of the articular surface

3) Formation of a subchondral cyst (due to leaking of the synovial fluid to the bones under pressure)

4) Subchondral thickening/sclerosis (due to the depositing of compensatory bone)

Question 13

How to manage osteoarthritis?

Answer 13

• It cannot be cured but delays it

1) The only treatment that decreases the symptoms would be a joint replacement

2) Functional treatment (physiotherapy):
- Limits the pain
- Increases the range of motion
- Increases the muscle strength

3) Exercise (helps in controlling weight, increases strength, improves and maintains function, and decreases pain, it is the best-studied non-pharmacological therapy)

Question 14

What is juvenile idiopathic arthritis?

Answer 14

A form of arthritis that can occur in young age groups

• It is a definitive arthritis of unknown origin that begins before the age of 16 and persists for 6 weeks at least

Question 15

What are the different classifications of Juvenile Idiopathic Arthritis?

Answer 15

• Distinguished based on the number of joints involved within the first 6 months of onset

1) Systemic arthritis: The entire body is affected from high spiking fever to joint discomfort

2) Polyarticular arthritis: Arthritis in five or more joints, with major symptoms of pain in the knees, ankles, wrist, fingers, elbows, and shoulders

3) Pauciarticular arthritis: arthritis in four or fewer joints, large joints like the knee, elbow, and wrist are affected

Question 16

What are the clinical manifestations of Juvenile Idiopathic Arthritis?

Answer 16

1) Swelling/synovial hypertrophy

2) Limited range of motion

3) Tenderness/warmth/redness of a joint

4) Gait disturbance

5) Fever, rash, serositis, red eyes

6) Anorexia, weight loss, and growth failure

7) Sleep disturbance, fatigue

Question 17

What are the different laboratory studies done for Juvenile Idiopathic Arthritis?

Answer 17

1) ANA (anti-nuclear antibodies) is frequently positive, which is usually found in SLE

2) Inflammation of the synovial fluid

3) X-ray: soft tissue swelling, periarticular osteoporosis, growth disturbance, loss of joint space

Question 18

What is meant by seronegative spondyloarthropathies?

Answer 18

A group of inflammatory arthropathies that shares distinctive clinical, radiographic, and genetic features which includes:

1) Ankylosing spondylitis
2) Reactive arthritis (Reiter’s disease)
3) Psoriatic arthritis
4) Enteropathic arthritis (Crohn’s, ulcerative colitis)

Question 19

What are the key features of seronegative spondyloarthropathies?

Answer 19

1) Inflammation of the axial arthritis (sacroiliitis and spondylitis)

2) Peripheral arthritis (often asymmetric and oligoarticular)

3) Absence of RF

4) HLA-B27 positivity

• All of the manifestations are immune-mediated and are triggered by a T-cell response which is presumed to be directed against an undefined antigen (which stimulates B-cells), but most likely are infections

Question 20

What is infectious arthritis?

Answer 20

• Can be bacterial, viral, fungal, mycobacterial or due to spirochaete
• Bacterial causes are divided into gonococcal and nongonococcal
• Gonococcal are more common but have less morbidity and mortality

Question 21

What is an example of infectious arthritis?

Answer 21

Septic (suppurative) arthritis

Question 22

Describe the pathogenesis of septic arthritis

Answer 22

1) The bacteria enters the joint via (Direct inoculation, hematogenous spread, or trauma)

2) The bacteria gets deposited into the synovial membrane

3) The bacteria enters the synovial fluid

4) The bacteria causes the joint to be purulent (pus)

Question 23

What is a septic (suppurative) arthritis?

Answer 23

• It is a devastating infectious disease that is not treated with antibiotics as the BV in the joints is destroyed
• The most dangerous and destructive monoarthritis
• It can destroy the cartilage within days
• It has a mortality rate of 7-15%, despite the use of antibiotics
• The organisms affecting this joint can be very virulent and can lead to a sort of septicemia and the patient could suffer from a septic shock that’s why there is an incidence of mortality, mainly staphylococcus and streptococcus

Question 24

What are the different diagnoses that can be a cause of arthritis?

Answer 24

1) Infection (bacterial, mycobacteria, fungal)

2) Gout

3) Pseudogout

4) Reactive arthritis

5) Osteoarthritis

6) Haemarthrosis

7) Lyme disease

8) SLE

9) Rheumatoid arthritis

• This is why the history of the patient is very important

Question 25

What is the difference between osteoarthritis and rheumatoid arthritis?

Answer 25

1) The pain in OA could be bilateral and it could be unilateral, unlike in RA which is usually symmetrical

2) The stiffness in OA will take less than 1 hour to loosen up compared to the RA which takes more than 1 hour

3) RA is usually between 25-50 while OA >40 years

4) RA develops within weeks or months, while OA develops slowly over many years

5) Osteophytes are present in OA and not in RA

6) AR is an autoimmune response affecting the synovial membrane which leads to the destruction of the joint, while OA is the loss of the cartilage matrix due to wear and tear

7) Rheumatoid factor is usually present in RA but not in OA